This is in regards to my recently purchased 2007 Lexus RX. Of the several warning lights displayed, the airbag light was of main concern. When I scanned the modules, I was presented with a B1787 from the Occupant Classification Module. My scan tool described the code as "collision event received from rear LH occupant detection sensor". I found this hard to believe, given the truck had no sign of ever being involved in an accident.
I decided to use ProDemand to look up the factory description of said code. Turns out, there's actually two possible causes: First was an actual collision event, with the second being the front passenger seat being struck hard enough to "fool" the module into thinking there had been a collision. I know the PO had kids, so I immediately assumed that at one point the front seat had been kicked hard enough to trigger a failure.
Per the OEM instructions, the first steps were to perform a zero point calibration of the weight sensor in the seat followed by performing the "sensitivity check" procedure. The zero point calibration was easy: seat at it's lowest position, seatback in the most upright position, headrest at the lowest position. The sensitivity check was slightly more tricky.... it begins by verifying that the weight sensor reads 0 pounds while unoccupied, followed by instructing the technician to place a 65 pound weight on the seat and verifying the displayed weight was 55-75 pounds.
Obviously, I didn't have a 65 pound weight on hand, so I used one and a half of my god given cheeks to put the appropriate amount of weight on the seat while watching the scan data. After successfully completing both procedures, I cleared the codes from the OCC module and the SRS module which to my delight extinguished the airbag indicator.
Being someone in the industry, there's nothing more satisfying than a free and simple fix! Just wanted to share, in case anyone comes across this issue in the future.
I decided to use ProDemand to look up the factory description of said code. Turns out, there's actually two possible causes: First was an actual collision event, with the second being the front passenger seat being struck hard enough to "fool" the module into thinking there had been a collision. I know the PO had kids, so I immediately assumed that at one point the front seat had been kicked hard enough to trigger a failure.
Per the OEM instructions, the first steps were to perform a zero point calibration of the weight sensor in the seat followed by performing the "sensitivity check" procedure. The zero point calibration was easy: seat at it's lowest position, seatback in the most upright position, headrest at the lowest position. The sensitivity check was slightly more tricky.... it begins by verifying that the weight sensor reads 0 pounds while unoccupied, followed by instructing the technician to place a 65 pound weight on the seat and verifying the displayed weight was 55-75 pounds.
Obviously, I didn't have a 65 pound weight on hand, so I used one and a half of my god given cheeks to put the appropriate amount of weight on the seat while watching the scan data. After successfully completing both procedures, I cleared the codes from the OCC module and the SRS module which to my delight extinguished the airbag indicator.
Being someone in the industry, there's nothing more satisfying than a free and simple fix! Just wanted to share, in case anyone comes across this issue in the future.